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Laser systems face massive economic challenges for cost effective, but yet ultraprecise assembly processes. Assembly costs are mainly driven by the demanding requirements of laser systems leading to challenging final assembly positions. Most challenging is the robust process control of the UV-curing adhesive bonding process. As a highly multifactorial process adhesive bonding processes are subject to a target conflict of rapid curing times within several seconds, robust mechanical properties required for reliable laser systems and before all a high reproducibility in terms of precision. The repeatability of adhesive bonding processes is limited by the shrinkage effects fast-curing adhesives inherit. The work presented aims for a significant reduction of the impact of shrinkage effects during curing and a resulting increase in assembly precision. Three key approaches are the enablers for robust bonding processes: Firstly, sophisticated curing systems tailored to the needs of the bonding task keep the variance of UV-radiation to a minimum. Therefore, the authors equip their self-developed micromanipulator with an UV-curing system. Secondly, the ultraprecise volumetric dispensing in Pico liter range with online-characterization of adhesive volume minimized variation in volume and dispensing position. The authors present a calibration station for contactless jet dispensing systems. Both volume and position are measured and adjusted automatically. Lastly, an automated characterization station for the measurement of adhesive shrinkage is presented. These technologies allow for highly reproducible adhesive bonding processes in automated production environments. They are deployed in Fraunhofer IPT’s prototyping projects and feasibility studies and Aixemtec’s assembly services and their automated assembly cells.
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